Submarine signaling apparatus



July 29, 1930, w: I... WALKER I SUBMARINE SIGNALING APPARATUS Original Filed Sept. 5, 1925 I 2 Sheets-Sheet 1 y 29, 1930. W. L. WALKER 1,111,591

susmnmm SIGNALING APPARATUS} Original Filed Sep11. 5, 1925 2 Shins-Sheet 2 INVENTOR. [WM 71917 L lVfll/fff /1/s ATTORNEYS Patented July 29, 1930 nu-Titan stars-s tartar caries WILLIAM L. WALKER, or NEW YORK; Y., assreuon T0 mama 'sreitnri -& EQUIP- MENT coerce-Arron, a CORPORATEON or n eawaaa SUBMARINE SIGNALING APPARATUS Application filed September 5, 1925, Serial No. 54599; Renewed Cato her 19, 19 29.

My invention relates particularly to apparatus used in submarine signaling systems in which a plurality of microphones or other sound receiving apparatus are alternately placed in circuit with telephones or other indicating devices at the receiving station.

This invention also relates to switches that are designed to control a plurality of such electric circuits by the movement of a single switch handle into various positions depending upon the apparatus or devices designed to be placed in operation, but is applicable to tion and effort on the part of the operator.

In the present application I have described the details of a preferred form of switch which I have found to be very eilicient and reliable in actual use and which may be installed within a small cabinet or box, together with other apparatus constituting the instruments employed in receiving submarine signals. The arrangement of the switches in relation to the other apparatus and instruments mentioned are described and claimed in my co-pending application, Serial No. 54,700 filed September 5, 1925.

In my present application I have described one arrangement of receiving circuits employed in receiving submarine signals and to which the s itches of the present invention are particularly adapted.

. For a detail description of the preferred form of my invention reference may behad to the following specification and to theatcompanying drawings forming a part thereof in which K p p s Fig. lis a side elevation of my improved switch showing the panel on which it is mounted in section; y

i Fig. 2 is a transverse sectional view taken substantially onthe li'ne2 =2 of Fig, 1, and

Fig. 3 is a similar transverse s itliial View taken substantially on the line of Fig, 1. Fig. 4 is ahorizontal or axial transverse sectional view taken substantially on the line l -:4 of'Fig. 1. 4 a p Fig. 5 isa side elevation of one" oft-he switch contact discs.

Fig. 6 is a side elevation of one of the slrort-circuit-ing discs. v

Fig. 7 is a side elevation of onefo' f the insulating washers which separate the contact discs, and p Fig. 8 is a schematic diagram of the; connections constituting the circuits in which the switches may be employed.

Referring to 8 of the drawings, circuit diagram firstbe described. The letters P B indicate the port b'ow inicrophone, S B the starboard bow microphone. P A the port aft microphone and S -A the starboard aft microphone. Obviouslyfinstead of having both how and aft micro- I phones, all of the microphones may be located at any other position inthe. length ofthe ship either midships or forward or aft in which case the letters A B indicate duplicate sets of microphones at the respective receivng points or ears of the receiving apparatus. Referring further'to Fig. 8, the numerals 1, 2, 3, 4L and 5 indicate respective Contact discs which are rigidly mounted on a central shaft hereinafter to be more -fully described so that they all turn simultaneously on said shaft, said discs being insulated from each other and from the shaft. Associated with each of the contact discs just referred to are a series of spring Contact brushesor fingers indicated in the various positions by the numerals 27 to 4:0 inclusive, and 44: and 4-5 which will bereferred to hereinafter. It will be noted that the crush 27 is adapted to bear 1 upon the manic ofth disc '5 at an times t rough an ar at slightly more han 9.0", while the brushes 31 and 35 are adap sate tear apes the use 5 only when the latter is ear ed aa teas-ea the iespeaive ipesiueae n 1 which they are heated, In this wa when the lower parties or the sites iueveugteward the right, the brushes 2? and 35 will as treetrically eeuuetea egether andjf the laser portion of the disc 5 be moved awn-u the the left, the brushes 27 and 31 will be connected together. This method of operation applies also to the discs 2, 3 and l. As regards the short circuiting disc 1, the brushes 4A- and 45 are connected together when the disc in position as indicated in Fig. 8, but when turned 45 neither brush will contact with said disc. The switch in the upper portion of Fig. 8 constituting the contact discs 6, 7 and 8, operates in a similar manner to the switch previously referred to. Contacts 21 and 26 are always in contact with the discs 7 and 8 respectively, while the contacts 23, 24 and are adapted to contact when the discs are rotated 45 either clockwise or counter-clockwise. The short circuiting disc 6 also connects the brushes 39, in the position shown in Fi .8 but when turned neither of said brushes contact witn said disc. Referring to the right hand of Fig. 8, the numeral 9 indicates a coil forming the winding of an audio frequency auto transformer. The numeral 10 indicates a condenser preferably of about 1 microfarad capacitance. The numerals 11, 12, 13 and 14 indicate the points to which connections are made with the auto transformer, and the numeral 15 indicates a switch for throwing the condenser 10 in shunt with the portion of coil 9. The numeral 16 indicates a condenser of about 2 microfarads capacitance. The numeral 1'? indicates an impedance or choke coil, the purpose of'which wi l be hereinafter described. The numeral 18- indicates switch. The numeral 19 indicates a condenser of about of a microfa-rad capacitance for preventing sparking between the contacts of the switch 18, and 20 indicates a battery for energizing; the microphones in the well-known manner. The numeral indicates a rheostat ha ing a series of contact points adapted to engage the movable arm 51 so that the auto transformer 9 may be shunted by more or less resistance depending upon the desired volume of the signals to be heard in the telephone.

Assuming now that it be desired to listen to the B microphone on the starboard side, the switch handles incicated on the extreme left of Fig. 8 are moved toward the left so that the pointer on the upper handle would indicate S and the pointer on the lower han dle would indicate B. These movements will connect the brush 21 wi h the brush the brush 26 with the brush 24-. he brush 3% with the brush 30, the brush 33 with the brush 29, the brush 32 with the brush and the brush 31 with the brush 2?. it will thus be seen that themicrophones P B and S B are so connected with the leads to the upper swi ch that either may benow thrown into circuit. The upper switch handle, however, having been turned toward S the contacts 22 and 24am connected with the discs 7 and 8 vrespectively, and the'microphone S B has been thrown into circuit by the movement of (the up ler switch. The brushes 21 and 26 are connected respectively with the battery 20 and with the choke coil 17, from Which the circuit passes through the lead 5;) to the switch 18 and back to the battery 20. Thus the microphone is energized by constant direct current of the battery 20. hen vibrations from the surrounding medium, such as sea wet are impressed upon the microphones, the current therein will be varied and the variable component of the current will be conducted through the lead 52 running to the connecting point 12 of the auto transformer 9, emergingat the connecting point 11, passin through the condenser 16 and thence to the battery through the lead 53 and switch 18, thus the primary circuit of the transformer 9 is energized according to the received ibrations of the signal. The alternating field thus produced in the transformer 9, results in increasing the voltage of the alternating current which is conducted to the telephone fO-llOWSZ Through the connecting point 14, the current passes through the conductors 54, 55 and 56 to the telephone The current then con-' tinues through the leads and 59 to the contact point 11 thus completing the circuit through the -tecondary windings of the auto transformer 9. Since the C' s l and 6 have been rotated as previousl described the cir-' cuits between contacts 35-) and a0 and between contacts stand have been broke and h n *e the telephone ('30 is not shunted. When the circuit has b 7 established through the microphone S as above de. .rihed, the volume of the sounds produced in. the telephones by niicrophonic action may be controlled in l-i following way This control is of especial at vantage where the received signals are accompanied by undesirable noises, such as water no. 1', propeller sounds and other noises which it is desired to distinguish from the musical note of subn'iarine signal. The reduction in the volume of sound will greatly reduce the un desirable noises without making the musical note of the signal inaudible. This reduction in the volume of the sound may be produced by moving the Contact 51 over the variable resistance 50. It will be noted that the latter resistance forms a shunt between the crtreine ends of the secondary coil of the auto trausfornn3 9. thus the less resistance introduced the more of the signal current will be shunted away from the telephones and the volume of the signal correspondingly reduced.

On the other hand should it be desired to increase the volume of the signals, the switch 15 may be closed throwing the condenser 10 into shunt with a portion of the auto transformer coil 9. I have found that, owing to some reason which I cannot. explain, the

introduction of this condenser in this man- I ner greatly increases the vol-urae'of the reiii-visas ceived sounds, particularly the sounds from a submarine oscillator or bell as distinguished from water and other noises. As above stated, this condenser has a capacitance of about 1 microfarad. After having tried condensers of various capacitance in the same position, I find that this capacitance is particularly well adapted for purposes above described. The effect of the condenser is apparently not one of resonance because the electrical constants of the circuit are not such as to bring about that result. As above stated, I cannot explain the reason for the increase in the volume of signals, but I have discovered that a condenser located as described has this function, to a remarkable extent. v 7

It will be apparent from the above description that by turning the upper switch handle toward the right so that the pointer will indicate the letter P, the port microphones will be thrown into circuit; inthis manner the port and starboard microphones may be compared as to their intensity and .owing to the shadow effect of the hull of the vessel on the microphones the approximate direction of the source of sound may be determined in accordance with the volume of the sounds received in the respective microphones. When the vessel is pointed toward. the source of sound, of course the volume of the sounds in: the respective port and starboard microphones will be equal. Obviously, compensating devices may be connected with the microphone circuits so as tov determine the direction of the sound, such as is described and claimed 1n my. co-pending application Serial No. 25,011, filed April 22, 1925. However. I do not consider the'latter necessary for the efficient operation of my improved signal, receiving system herein described.

It will furthermore be understood that by turning the lower switch in Fig. 8 toward the left so that the pointer indicates the letter A, the contact brushes on the discs 2', 3 4 and 5 will cause the microphones P A and S A to be connected with the upper switch, through which the respective starboard and port microphones of the A or aft group may be selected. It will be noted that when the discs land 6 are turned from the positions shown in Fig. 8, neither of the sets of contact brushes will engage said discs but when said discs are turned slightly in either direction from the position last noted, the contact brushes will immediately contact with the said discs, the contacts liand 45 being connected with the leads and 57 of the telephone 60, movement of the disc 1 will short circuit the telephone. This prevents any click or sudden sounds being in the telephones when the contacts between the discs 2, 3, 4; and 5 are broken. In a similar manner the brushes 39- and 4&0 short produced circuit the telephones when the disc 6 is turned simultaneously with, the discs 7'6 and 8. The details of the switch for producing the above mentioned connections'w-ill now be described.

Referring to Fig. 1, the. numeral 61 indicates a supporting panel preferably made; of

insulating material to which is attached one of the end plates or frames 62 of the switch structure; this frame is connected with the end in a reduced portion '69 on which is'secured the operating handle'TO. The hub of said handle. is preferably provided-with a pointer 71 to indicate the positions of the handle when the. various microphones are in circuit, as indicated at the extreme left of Fig. 8. The shaft 68: is screw threaded on each end as indicated at 72 and 7 3, and is surrounded by insulating sleeve On the screw threaded portion 73 is a disc 75 which is adapted to be retained rigidly in position by a set screw. 7 6 or other suitablemeans. The screw threaded portion 72 of shaft 68 also carries a disc 77 against which bears a retaining nut 78. I The'ri ght hand disc 75 is provided on its periphery with a series of transverse grooves 79 shown in dotted lines in Figs. 2 and 3, and in section in Fig.4. These grooves are adapted to receive a small roller 80, indicated in Figs. land 4, mount- 5-:

ed onthe end of a spring arm '81 which is attached to the longitudinal supporting plate 65. This serves to indicate to the operator when the switch has been turned accurately to any one of the three positions in which it is intended to be placed, because the roller Y entering the grooves retards the rotation of the switch at definite points. The end discs or plates 7 5 and 77 are connected by longitudinal rods 82, which, passing throughcorresponding holes in the various contact discs and washers, serve to hold them accurately in position on" the shaft- 68. The holes through the conducting discs'l to. 5 inclusive, as well as 6; to 8 inclusive, have insulating bushings as indicated at 83, FigsLS and 6. The end disc 75 is provided with a screw 84 forming a stop to limit the rotation of the switch when contacting with the screws 85 and 86: on the. end plate 62.. The. contact iscs of the switches having been assembled in. therelative positions as-indicated in Fig". 8, thesame are thus mounted rigidlyon the shaft 68;- Which is inserted between the end plates 62 and 63 so, that the spring lingers; 2i 1 to 45 inclusive. contact with the. portions of said conducting discs which project: above the insulating discs, as. indicated-in Figs. 1, 2 and 3. These spring fingers or brushes are monnt'e'd'i ipon the longitudinal strips 61%,. 6 5 ii}?! and 66 respectively, and are, of course, each insulated from said strips by suitable insulating sheets and bushings as indicated in Fig. 2. The machine screws which hold these brushes in position are provided with pairs of nuts which form the means for connecting the leads with the respective brushes as indicated at 87 in Figs. 2 and 3, the connections being made with said brushes as shown diagrammatically in Fig. 8.

From the above description it will be appreciated that I have produced a simple and efficient system for receiving-sound signals and have included therein, switches of compact, efficient and durable design which may be installed in a comparatively small space, such asin a receiving cabinet of a type indicated in. my co-pending application, Serial No. 5%.700 above referred to.

Having thus described this form of my invention, I do not wish to be understood as being'limited to the details of form and arrangements of parts and circuits indicated therein, for various changes may be made by those skilled in the art without departing from the spirit and scope of my invention a set forth in the accompanying claims.

What I claim and desire to protect by Letters Patent is:

1. Apparatus for receiving sound signals.

comprising, means for receiving sound waves and converting the same into correspondingly varying electric currents, a transformer, a switch for connecting said transformer in circuit with said receiving means, a condenser having greater capacity than that necessary for resonance at the frequencies to be re ceived, being thereby adapted to eliminate extraneous noises, a switch for connecting said condenser with a portion of the secondary of said transformer and means in circuit with said transformer for detecting the variable currents produced by the vibrations of the received sounds.

2. Apparatus for receiving sound signals comprising, means for receiving sound waves and converting the same into correspondingly varying electric currents, an auto-transformer, a switch for connecting the primary winding of said transformer with said receiving means, means in circuit with the secondary winding of said transformer for detecting the variable currents produced by the vibrations of the received sounds, a condenser having greater capacity than that necessary for resonance at the frequencies to be received, being thereby adapted to eliminate extraneous noises, and a switch for connecting said condenser in shunt with a portion of the secondary of said transformer.

3. Apparatus for receiving sound signals comprising, a plurality of devices for receiving sound waves and converting the same into correspondingly varying electric currents, a transformer, a switch for selecting and connecting groups of said devices successively with said transformer, a conden er having greater capacity than that necessary for resonance at the frequencies to be received, being thereby adapted to eliminate extraneous noises, a switch for connecting said condenser With a portion of the secondary of said transformer and means in circuit with said transformer for detecting the variable currents produced by the vibrations of the received sounds.

Apparatus for receiving sound signals comprising, a plurality of devices for receiv ing sound waves and converting the same into correspondingly varying electric currents, a transformer, a switch for selecting and connecting groups of said devices successively with said transformer, a second switch for selecting and connecting the individual receivin g devices of said groups with said transformer, a condenser having greater capacity than that necessary for resonance at the frequencies to be received, being thereby adapted to eliminate extraneous noises, a switch for connecting said condenser with a portion of the secondary of said transformer and means in circuit with said transformer for detecting the variable currents produced by the vibrations of the received sounds.

5. Apparatus for receiving sound signals comprising, a plurality of devices for receiving sound waves and converting the same into correspondingly varying electric currents, an auto-transformer, a switch for selecting and connecting groups of said devices successively with the primary Winding of said transformer, means in circuit with the secondary winding of said trai'isformer for detecting the variable currents produced by the vibrations of the received sounds, a condenser having greater capacity than that necessary for resonance the frequencies to be received, being thereby adapted to elimmate extraneous noises, and a switch for connecting said condenser in shunt with a portion of the secondary of said transformer.

6. Apparatus for receiving sound signals comprising, a plurality of devices for receiving sound waves and converting the same into correspondingly varying electric currents, an auto-transformer. a switch for selecting and connecting groups of said devices successively with the primary winding or said transformer, a second switch for selecting and connecting the individual receiving devices of said groups with the primary winding of said transformer, means in circuit with the secondary winding of said transformer for detecting the variable currents produced by the vibrations of the received sounds, a condenser having greater capacity than that necessary for resonance at the frequencies to be received, being thereby adapted to eliminate extraneous noises, and a switch for connecting said condenser in shunt with a portion of the secondary of said transformer.

7. Apparatus forcreceiving sound signals comprising, means for receiving sound waves and converting the same into correspondingly varying electric currents, a trans- V former, a switch for connecting said transformer in circuit with said receiving means, means in circuit with said transformer for detecting the variable currents produced by the vibrations of the received sounds, a condenser having greater capacity than that necessary for resonance at the frequencies to be received, a switch for connecting said condenser in shunt with a portion of the secondary of said transformer to eliminate e1;- traneous noises and a variable resistance in shunt with the secondary of said transformer to vary the volume of the received signals.

8. Apparatus for receiving sound signals comprising, a plurality of devices for receiv-' ing sound waves and converting the same into correspondingly varying electric currents, a transformer, a switch for selecting and connecting groups of, said devices successively with said transformer, means in circuit with said transformer for detecting the variable currents produced by the vibrations of the received sounds, a condenser having greater capacity than that necessary for resonance at the frequencies to be received, a switchfor connecting said condenser in shunt with a portion of the secondary of said transformer to eliminate extraneous noises and a variable resistance in shunt with the secondary of said transformer to vary the volume of the received signals. I

9. Apparatus for receiving sound signals comprising, a plurality of devices for receiving sound waves and converting the same into correspondingly varying electric currents, a

transformer, a switch for selecting and connecting groups of said devices successively with said transformer, a second switch for selecting and connecting the individual receiving devices of said groups with said transformer, means in circuit with said trans former for detecting the variable currents produced by the vibrations of the received sounds, a condenser having greater capacity than that necessary for resonance at the frequencies to be received, a switch for connecting said condenser in shunt with a portion of the secondary of said transformer to eliminate extraneous noises and a variable resistance in shunt with the secondary of said transformer to vary the volume of the received signals.

10. Apparatus for receiving sound signals comprising a plurality of devices for receiving sound waves and converting the same into correspondingly varying electric currents, an auto-transformer, a switch for selecting and connecting groups of said devices successively with the primary winding of said transformer, means in circuit with the secondary shunt with a portion ofthe secondary of said transformer to eliminate extraneous noises, and a variable resistance in shunt with the secondary of said transformer to vary the volume of the received signals.

11. Apparatus for receiving sound signals comprising a plurality of devices for receiving sound Waves and converting the same into correspondingly varying electric currents, an auto-transformer, a switch for selecting and connecting groups of said devices successively with the primary winding of said transformer, a second switch for selecting and connecting the individual receiving devices of said groups with the primary winding of said transformer, means in circuit with the secondary winding of said transformer fordetecting the variable currents produced by the vibrations of there ceived sounds, a condenser having greater capacity than that necessary for resonance at the frequencies to be received, a switch for connecting said condenser in shunt with a portion of the secondary of said transformer to eliminate extraneous noises, and a variable I resistance in shunt with the secondary of said transformer to vary the volume of the received signals.

Signed at New York this 2nd day of September, 1925. I

' lVILLIAM L. WALKER. 

